Magnetic aftereffect in SmCo/sub 5/ sintered magnets machined to small size

The magnetic aftereffect was measured for SmCo/sub 5/ sintered magnets. The effects of machining down to small size and to heat treatment were investigated. Marked magnetic aftereffect and permanent deterioration were observed. It was found that the magnetic aftereffect could be reduced by heat treatment to about 1/2 and the permanent deterioration to about 1/3. In contrast, the aftereffect constant, which is the coefficient of logarithmic time decay, remained constant irrespective of heat treatment.<
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